Re: btrfs partition converted from ext4 becomes read-only minutes after booting: WARNING: CPU: 2 PID: 2777 at ../fs/btrfs/super.c:260 __btrfs_abort_transaction+0x4b/0x120

[Chris Murphy <lists@colorremedies.com>]

On Thu, Jun 25, 2015 at 8:08 PM, Qu Wenruo <quwenruo@cn.fujitsu.com> wrote:

> A quite code search leads me to inline extent.
>
> So, if you still have the original ext* image,
> would you please try revert to ext* and then convert it to btrfs again?
>
> But this time, please convert with --no-inline option, and see if this
> remove the problem.

Using -n at convert time does not make a difference for the
btrfs-convert bugs I've opened:
https://bugzilla.kernel.org/show_bug.cgi?id=101191
https://bugzilla.kernel.org/show_bug.cgi?id=101181
https://bugzilla.kernel.org/show_bug.cgi?id=101221
https://bugzilla.kernel.org/show_bug.cgi?id=101231

The last one I just discovered happens much sooner, is easier to
reproduce than the other two. It's a scrub right after a successful
btrfs-convert that btrfs check says is OK. But the scrub ends with two
separate oopses and multiple call traces and a spectacularly hard
kernic panic (ssh and even the console dies).

So I think btrfs-convert has a bug, but then the kernel code is not
gracefully handling it at all either and crashes badly with a scrub;
and less badly with balance. However, the file system is still OK
despite scrub crash. With balance failure, the file system is too
badly damaged and btrfs check and btrfs-image fail.



-- 
Chris Murphy